Technical Field
The present invention relates to a sealing member of a tube-shaped battery and the tube-shaped battery with the sealing member.
Related Art
A tube-shaped battery has been widely used as a battery as a power supply of various electrical appliances. The tube-shaped battery has a basic configuration formed by sealing an opening of a bottomed tube-shaped battery can storing a power generating element with a metallic sealing plate to seal the battery can, and is attached with an electrode terminal. Such a tube-shaped battery is used for small-sized appliances, such as cellular phones, notebook computers, and digital cameras, and is also used as a power source of such as electric vehicles and hybrid vehicles. In either of the uses, the tube-shaped battery is required to have a high degree of sealability to be able to certainly prevent leakage of the battery's contents.
From the viewpoint of ensuring the above sealability, for example, in Japanese Patent Application Laid-open Publication No. 2008-251213, there is proposed a sealed battery including an electrode external terminal provided with a columnar inserting part, an insulating gasket, and a sealing plate, and these parts are tightened integrally with the columnar inserting part, and is configured provided with an annular protruding part that contacts the insulating gasket from the front and the back and does not easily leak liquid even when vibration or impact is applied. Further, in Japanese Patent Application Laid-open Publication No. 2008-270167, there is proposed a sealed battery having a similar configuration to that in the former patent reference, configured with a recess part that corresponds to a horizontal section shape of the columnar inserting part provided to the insulating gasket. Thus, it is asserted that sealability may be further increased.
In the above patent references, however, the insulating gasket is pressed with the annular protruding parts or the columnar inserting part in order to increase sealability. Thus, the insulating gasket is compressed and slightly expanded outwards when tightened and fixed with the columnar inserting part, and sufficient sealability with the force of repulsion of the insulating gasket could not be obtained.